Butterflies and the late bloomer

A pair of Gulf Fritillary butterflies sample the nectar of one of my Giant Mexican Sunflowers (tithonia diversifolia). The flowers are Fall bloomers and come on after the regular Mexican Sunflowers pretty much go into demise for the Fall and Winter. This morning the low hit 28 degrees bringing the first freeze of the season and I wonder how long these flowers or the butterflies will still be around this year.